Cockburn C G, Fitzsimmons C M, Barnes M J
Strangeways Research Laboratory, Cambridge, UK.
Thromb Haemost. 1989 Jun 30;61(3):378-85.
The binding of fn to collagen (type I) fibres has been found to resemble that of vWf in the following respects: Binding is rapid, specific, saturable, similar at 4 and 37 degrees C, and reduced by increasing ionic strength. Binding is not inhibited by native, monomeric collagen, suggesting a multivalent mechanism of interaction. Binding of fn occurs to a variety of collagen fragments (after their renaturation and polymerization), including, for example, the collagenase-derived TCA and TCB 3/4 and 1/4 molecular fragments and the peptides alpha 1(I)CB3, 6b, 7 and 8 obtained by cleavage with cyanogen bromide (CB), suggesting a wide distribution of binding sites on the native collagen molecule. As judged by the effect of heat-treatment, the native conformation of fn is required. Chemical modification indicates the involvement of arginyl residues in collagen and carboxyl groups in fn. However, fn and vWf did not compete with one another in binding to collagen, suggesting the participation of different collagen arginyl residues in the two interactions. Fn-binding differed from that of vWf in that the former was inhibited by denatured monomeric collagen (gelatin). Fn-binding was also inhibited by the fragment TCA in denatured form. The inhibitory activity was lost after chemical modification of arginyl residues in gelatin. Our results suggest that fn binding to collagen fibres and gelatin involves the same widely-distributed spectrum of binding sites.
已发现纤连蛋白（fn）与I型胶原纤维的结合在以下方面类似于血管性血友病因子（vWf）：结合迅速、具有特异性、可饱和，在4℃和37℃时相似，并且随着离子强度增加而降低。天然单体胶原不会抑制结合，提示存在多价相互作用机制。fn可与多种胶原片段（复性和聚合后）结合，例如，包括胶原酶产生的TCA和TCB 3/4和1/4分子片段，以及通过溴化氰（CB）切割获得的肽α1（I）CB3、6b、7和8，提示在天然胶原分子上结合位点分布广泛。从热处理的效果判断，需要fn的天然构象。化学修饰表明胶原中的精氨酰残基和fn中的羧基参与其中。然而，fn和vWf在与胶原结合时并不相互竞争，提示在这两种相互作用中不同的胶原精氨酰残基参与其中。fn的结合与vWf不同，因为前者会被变性单体胶原（明胶）抑制。fn与变性形式的片段TCA结合也受到抑制。明胶中精氨酰残基经化学修饰后，抑制活性丧失。我们的结果提示，fn与胶原纤维和明胶的结合涉及相同的广泛分布的结合位点谱。
